1. Field of the Invention
The present invention relates to a display device, and more particularly to the terminal structure of signal lines.
2. Description of the Related Art
An active matrix type display device is, for example, configured such that respective pixels which are mounted on a substrate include switching elements respectively, a scanning signal which is supplied to gate signal lines turns on the switching elements of the respective pixels arranged in parallel in rows, and a video signal which is supplied to drain signal lines through the respective switching elements is supplied to the respective pixels.
Due to such a constitution, in a periphery of a display part which is constituted of a mass of the above-mentioned pixels, terminals for supplying the scanning signal to the respective gate signal lines, terminals for supplying the video signal to the respective drain signal lines are respectively formed in parallel to each other.
Here, the respective terminals are constituted such that at terminal portions of the signal lines which are covered with an insulation film, holes are formed in the insulation film so as to expose portions of the signal lines, and a conductive layer is formed such that the conductive layer covers the exposed portions of the signal lines and peripheries of the insulation film in which the holes are formed.
Further, the display device having such a constitution is usually manufactured such that a substrate which is slightly larger than the above-mentioned substrate is used, signal lines which extend in the direction opposite to the pixel side are formed on the respective terminals, the respective signal lines are connected in common by another wiring layer, and a portion of the substrate on which the wiring layer is formed is cut away together with the substrate before completion of the manufacturing.
The respective signal lines are connected in common by the wiring layer for dispersing static electricity to the respective signal lines through the wiring layer when the static electricity intrudes into one terminal, for example, so as to prevent the breakdown of the switching element attributed to the electrostatic electricity.